Raisable landing gear of this type, in which the set of wheels may be implemented in the form of a tilting bogie, extends essentially vertically (in the landing gear down position) so as to avoid any risk of the sliding rod jamming because of excessive shear forces being exerted on said sliding rod. The lateral positioning of such landing gear (also referred to as "main" landing gear) on either side of the longitudinal midplane of an airplane is generally selected to be in a determined region of each wing, at a distance from the longitudinal midplane that is sufficient to ensure that the airplane has sufficient lateral stability while taxiing, in particular while turning.
However, the further the wing landing gear is located from the longitudinal midplane of the airplane for the purpose of increasing lateral stability during taxiing, the greater the length of the landing gear (because of the dihedral angle of the wings), and this naturally has a direct effect on weight. Furthermore, the load per wheel is limited in order to allow for the strength of the runway. With large-capacity transports (mass greater than 250 tons), it is possible to provide main wing landing gear in the form of two four-wheel sets, together with a central landing gear set having two wheels (diabolo) which provides a better spread of load during taxiing and take-off.
Attempts are being made at present to reduce the weight of structures and equipments more and more in order to obtain maximum performance and greater range, and in particular in order to use landing gear that is as short as possible. However, persons skilled in the art know that wing landing gear must be placed at a adequate distance from the longitudinal midplane of an aircraft to ensure that lateral stability remains satisfactory while taxiing.